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If 10⁹ electrons leave a body every second, the time required to accumulate a total charge of 1 C is approximately:
A200 days
B200 hours
C200 years (≈ 6.25 × 10⁹ seconds)
D2 hours
Answer & Solution
Correct answer: C. 200 years (≈ 6.25 × 10⁹ seconds)
Charge per second: 10⁹ × 1.6 × 10⁻¹⁹ = 1.6 × 10⁻¹⁰ C/s. Time for 1 C: 1 / (1.6 × 10⁻¹⁰) = 6.25 × 10⁹ s = 6.25 × 10⁹ / (365 × 24 × 3600) ≈ **198 years ≈ 200 years**. Shows 1 C is a very large unit for electrostatics.
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